Fluids based on fluorocarbon compounds are widely used in vapor-compression heat-transfer systems, especially air-conditioning, heat-pump, refrigeration or freezing devices. The common feature of these devices is that they are based on a thermodynamic cycle comprising vaporization of the fluid at low pressure (in which the fluid absorbs heat); compression of the vaporized fluid up to a high pressure; condensation of the vaporized fluid to liquid at high pressure (in which the fluid expels heat); and depressurization of the fluid to complete the cycle.
The choice of a heat-transfer fluid (which may be a pure compound or a mixture of compounds) is dictated firstly by the thermodynamic properties of the fluid, and secondly by additional constraints. Thus, a particularly important criterion is that of the environmental impact of the fluid under consideration. In particular, chlorinated compounds (chlorofluorocarbons and hydrochlorofluorocarbons) have the drawback of damaging the ozone layer. Non-chlorinated compounds are therefore now generally preferred, such as hydrofluorocarbons, fluoro ethers and fluoro olefins.
It is also still necessary to develop other heat-transfer fluids which have a global warming potential (GWP) lower than that of the heat-transfer fluids currently used, and which have equivalent or improved performance qualities.
Document US 2005/0 188 697 describes the use of polyfluoro ethers such as 1-methoxyheptafluoropropane (or HFE-7000) as heat-transfer fluid.
Document WO 2010/100 254 describes the use of various tetrafluorobutenes and especially 2,4,4,4-tetrafluorobut-1-ene (HFO-1354mfy), in various applications, including that of heat transfer.
Document WO 2011/050 017 describes the use of HFO-1354mfy as an expansion agent. The document mentions a list of other expansion agents that can optionally be used in combination with HFO-1354mfy. HFE-7000 features in this list.
There is still a need to develop other heat-transfer fluids that are less harmful to the ozone layer and that have a relatively low GWP, in order to replace the usual heat-transfer fluids.